In PFBC skin specimens, argyrophilic granular deposits partially colocalized with CD31+ structures (Fig. 1Y,Z); in particular, argyrophilic grains colocalized with CD31+ endothelial cell cytoplasm, but they were also found below and around endothelial cells, within the basal lamina. This evidence concerns the gene PECAM1 and bilateral striopallidodentate calcinosis.